The majority of dolls manufactured through the years have provided some type of artificial or simulated hair to enhance the realism and play appeal thereof. In the most common type of doll hair used in recent years, a plurality of thin filaments formed from materials such as polypropylene nylon or spun saran are grouped into bundles of approximately ten to forty filaments each to form a "yarn" which is then rooted within the doll head in a highly automated process in which the yarn bundles are secured at spaced intervals to the doll's head in a fixed attachment. Typically, the machinery which performs the rooting operation also cuts the yarn at the desired length to provide the appearance of typical human hair. In general, the filaments used in artificial doll hair have diameters of approximately one to three one thousandths of an inch with the diameter being selected in accordance with the economic and appearance factors considered by the manufacturer.
In most dolls it is desired that in addition to rooting a head of hair, the hair be given some styling or curling for enhanced appearances. The typical materials mentioned above may be curled by the manufacturer prior to purchase using heat setting curling factors which impart a more or less "permanent" curl or style to the hair filaments. While the methods and parameters of such heat setting are, to some extent, a matter of manufacturer's choice, generally speaking the manufacturer uses one or more heated mandrels upon which the hair is wound and thereafter heated above the material's glass transition temperature. Typical temperatures for the materials most commonly used are approximately one hundred and ninety to two hundred degrees Fahrenheit. The hair is then cooled while on the mandrel to permit the material to retain its established curl or set afterwhich the mandrels are removed and the hair styling is completed by careful manipulation. Such artificial hairs of the materials typically used may, in some instances, be set or styled using setting gels in which the chemical properties of the hair are altered temporarily by the application of setting gel to groups of hair fiber wound about styling mandrels or the like. Thereafter, the hair dries and retains its newly acquired set.
The problem with the commercially available hair fibers and methods of styling and setting used therein is that they are very intolerant of further use and manipulation by the child user such as combing, brushing, resetting and similar anticipated play patterns. Most presently available hair materials once set are not easily combed to a straight condition or "combed out" and instead often become brittle, broke and, in some cases, matted or tangled. Once combing or brushing is accomplished notwithstanding the accompanying hair damage, it is not susceptible to restyling or recurling without the reapplication of heated mandrels or setting gels. In general, manufacturers and consumer groups have considerable objection to doll playsets which require heated mandrels or curling irons or sometimes caustic and unpleasant setting gels being placed in hands of young children. As a result, very little if any success has been realized in providing realistic synthetic hair for dolls which facilitates repeated comb-outs and restyling in a satisfactory, safe and convenient manner.
Faced with need for restylable combable artificial hair, practitioners in the art have attempted various processes and compositions with very little success thus far. It has been found that attempts to crimp and curl a variety of thermal plastic polymers of the type available from conventional melt spin processes have been unsuccessful due to the limited number of polymers which can be successfully manufactured by melt spinning to fibers resembling human hair. Certain amorphous polyester polymers are capable of melt spin manufacture but have, when subjected to styling and manipulation, been found unsatisfactory upon repeated stressing and have suffered breakage and created a "frizzled" appearance due to the irreversible deformation caused by attempts to style and comb-out the doll hair.
Another approach tried by practitioners in the art has involved the use of plastic coated thin wire either alone or in combination with conventional hair fibers. While the plastic coated wire provides the malleability and "posability" desired, it has a generally short life and becomes quickly broken when repeatedly bent during styling. In addition, such plastic coated wire hair generally is subject to combing difficulties and becomes tangled, matted, broken or simply cannot be combed after several hairstyles or sets have been imposed.
The need for evermore improved play friendly and more usable synthetic hair for dolls has prompted practitioners in the art to attempt a number of approaches. For example, U.S. Pat. No. 3,955,587 issued to Dunn, et al. sets forth a CHANGEABLE SHAPE HAIR PIECE AND METHOD OF STYLING AN ARTIFICIAL COIFFURE in which a plurality of ductile filaments such as 37 to 43 gage plastic coated wire are distributed throughout hair filaments in a manner such that a small number of such ductile filaments may provide a setting or holding force to influence a large number of standard synthetic hair filaments. The hairstyle of the doll may then be reshaped by deforming the standard hair and ductile filaments using manipulation tools similar to hair rollers and the like.
U.S. Pat. No. 3,750,682 issued to Bonafiglia, et al. sets forth HAIR PIECES, WIG AND LIKE PRODUCTS which are formed having the predominant hair simulating fiber formed of a blend of nylon-6 and polyalkyl methacrylate which is formed into a filamentary material and used to form a wig or the like.
U.S. Pat. No. 3,614,843 issued to Hawtin, et al. sets forth ARTIFICIAL HAIR for use in a hair piece comprising a plurality of filaments of synthetic or regenerated polymeric material such as cellulose triacetate formed in filaments having hollow interior construction as either ring or open ring cross sections.
U.S. Pat. No. 3,433,235 issued to Doolittle sets forth a DECORATIVE FEMALE HAIR PIECE in which a plurality of malleable tongues are secured to a base member in a replaceable attachment. Each hair tongue is surrounded by a plurality of synthetic fibers and retains the shape of the malleable tongue to permit styling thereof.
U.S. Pat. No. 3,910,291 issued to Kim sets forth an ARTIFICIAL HAIR AND METHOD FOR MANUFACTURING THE SAME for use in wigs and the like comprising a multiplicity of synthetic fibrous yarns each formed with a plurality of small waves having various sizes and extending in various directions. Also, set forth is a method for manufacturing such artificial hair which includes the steps of forming and treating the synthetic fibrous yarns to create the small waves thereon.
U.S. Pat. No. 4,302,491 issued to Papageorgiou sets forth a HAIR SIMULATING FIBER formed of a composite which includes a metallic core member coated with a plastic material to form a fine strand. The core member and/or the coating member may be flattened to provide a strand which will exhibit curling characteristics and may be readily styled by an operator.
U.S. Pat. No. 2,517,349 issued to Raditz sets forth an ARTIFICIAL MUSTACHE CONSTRUCTION in which a synthetic mustache includes a pair of elongated malleable metal frames extending outwardly from the center portion of the fiber bundle to provide a malleable support for each half of the artificial mustache.
The foregoing described prior art synthetic hair fabrications and methods have enjoyed limited success and have not, to date, provided the highly desirable characteristics of a posable or cold set synthetic hair fiber suitable for use in dolls or the like. There remains, therefore, a continuing need in the art for evermore improved and more realistic synthetic hair fibers for doll hair which facilitate and tolerate repeated setting and combing out without becoming matted, tangled, brittle or broken.